When a small Local Area Network (LAN), such as a domestic network in a private residence, is linked to a larger network such as the internet, the link is often through a gateway router acting as a firewall. One of the functions of the firewall is to protect the LAN from intrusion from outside. In order to fulfill this function, firewall routers, especially firewall routers that are likely to be used by relatively technically unsophisticated users, tend to be preconfigured by their manufacturers to be very unwelcoming to unexpected communications from outside. Typically, the firewall is configured not to allow any internet connection that is initiated from the outside.
Gateway routers are available that can be configured using the “Universal Plug and Play” (UPnP) protocol by a server (or other device on the protected side of the gateway) to forward incoming connections. However, most router manufacturers turn that function off by default, for security reasons. The user could enable that function by configuring the router manually, or could configure the router manually to allow a connection on a specific port to a specific router on the protected side of the gateway, but such configuration requires a degree of sophistication in the operation of computer networks.
However, some users do wish to allow at least limited access to their LANs from outside, for example, to a server. Many users who wish to permit an incoming connection to a home server or other server on a small LAN do not have, and do not wish to have to acquire, the technical skill and knowledge to configure a router manually.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.